This is the failed shutdown look like:
So I tried the M$ shutdown.exe utility, anyone can get it there: http://www.petri.co.il/download_free_reskit_tools.htm
Described there: http://support.microsoft.com/kb/317371
...and transformed their "shutdown /l /t:120 "The computer is shutting down" /y /c" to simple:
shutdown /l /y /c
After 30 sec countdown the computer ended up in exactly the same situation as showed above and as the Fileuploader do. In the end, this is the NOT a Fileuploader bug, but rather some system bug on my end.
I heard that ACPI must be working and IMHO it does, so I did not understand, but that is another story